What can increase the risk of infertility?

Women in the US are delaying childbirth into their third and fourth decades of life. For couples trying to achieve pregnancy where the age of the woman is 35 or older, approximately one third of those may have fertility problems. An age over 35 increases the risk of fertility issues directly because of decreasing egg numbers and quality, but age also increases infertility because of the risk of other health conditions interfering with pregnancy, increased risk of genetic abnormalities causing miscarriages, and an increased risk of miscarriages overall. Other causes of infertility include extremes of weight (extremely underweight or overweight), smoking, alcohol use or abuse, extreme states of stress (physical or emotional), or any medical condition that may cause loss of regular menses.